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DAG witness in two servers

Arabsoft_AD
Arabsoft_AD asked
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Dear All,

I have two exchange 2010 servers installed, DAG configured.

I need to ask, do I can place the witness file on two servers for DAG; this is in case that; the first server which includes DAG witness file fails, the DAG will not fail.

Thanks
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Awarded 2009
Top Expert 2010

Commented:
The witness server must not be one of the servers that are part of the DAG.
See my article here on how to configure a DAG: http://www.experts-exchange.com/articles/Software/Server_Software/Email_Servers/Exchange/High-Availability-Exchange-2010.html
AkhaterSolutions Architect

Commented:
If the share witness fails your DAG will not fail you will need to lose 2 out of 3 voters to lose quorum

Author

Commented:
Hi demazter,
The witness server is not part of exchange servers, it's in file server. I'm asking if we can duplicate the witness folder in another server.

Hi Akhater,
Can you please tell me more details about what you mentioned?

Thanks All
AkhaterSolutions Architect

Commented:
What i meant is that the share witness is there to make the number of "voters" odd (3 in your case)

so if you lose only one of the voters (a mailbox server or the Share witness) you won't lose quorum and your dag will still operate normally. However if you lose simultaneously a mailbox server and the share witness then you will lose quorum and the DAG will be down.

all this being said you can assing an alternate share witness using EMC Set-DatabaseAvailabilityGroup -AlternateWitnessDirectory

more info http://technet.microsoft.com/en-us/library/dd297934.aspx

Author

Commented:
Thanks Akhater. Do you can help me on the command which i can use it to duplicate the witness in another server
Solutions Architect
Commented:

set-DatabaseAvailabilityGroup DAGName -AlternateWitnessServer OtherServer -AlternateWitnessDirectory C:\DAGFileShareWitnesses

Author

Commented:
ok, it will work, is it tested?

do i can apply now?
AkhaterSolutions Architect

Commented:
yes it will work and yes it is tested.

I don't know what you mean by "can I apply now"